Scores of civilian deaths over the past months from heavy American and allied reliance on airstrikes to battle Taliban insurgents are threatening popular support for the Afghan government and creating severe strains within the NATO alliance.

Afghan, American and other foreign officials say they worry about the political toll the civilian deaths are exacting on President Hamid Karzai, who last week issued another harsh condemnation of the American and NATO tactics, and even of the entire international effort here.

What angers Afghans are not just the bombings, but also the raids of homes, the shootings of civilians in the streets and at checkpoints, and the failure to address those issues over the five years of war. Afghan patience is wearing dangerously thin, officials warn.

The civilian deaths are also exposing tensions between American commanders and commanders from other NATO countries, who have never fully agreed on the strategy to fight the war here, in a country where there are no clear battle lines between civilians and Taliban insurgents.

At NATO headquarters in Brussels, military commanders and diplomats alike fear that divisions within the coalition and the loss of support among Afghans could undermine what until now was considered a successful spring, one in which NATO launched a broad offensive but the Taliban did not.

“There is absolutely no question that the will and support of the Afghan people is vitally important to what we do here,” Gen. Dan K. McNeill, the American commander of the International Security Assistance Force, said in an interview. “We are their guests, they are the hosts. We have to be mindful of their culture, we have to operate in the context of their culture, and we have to take every possible precaution to not cause undue risk to those around us, and to their property.”

But American officials say that they have been forced to use air power more intensively as they have spread their reach throughout Afghanistan, raiding Taliban strongholds that had gone untouched for six years. One senior NATO official said that “without air, we'd need hundreds of thousands of troops” in the country. They also contend that the key to reducing casualties is training more Afghan Army soldiers and police officers.

The anger is visible here in this farming village in the largely peaceful western province of Herat, where American airstrikes left 57 villagers dead, nearly half of them women and children, on April 27 and 29. Even the accounts of villagers bore little resemblance to those of NATO and American officials — and suggested just how badly things could go astray in an unfamiliar land where cultural misunderstandings quickly turn violent.

The United States military says it came under heavy fire from insurgents as it searched for a local tribal commander and weapons caches and called in airstrikes, killing 136 Taliban fighters.

But the villagers denied that any Taliban were in the area. Instead, they said, they rose up and fought the Americans themselves, after the soldiers raided several houses, arrested two men and shot dead two old men on a village road.

After burying the dead, the tribe's elders met with their chief, Hajji Arbab Daulat Khan, and resolved to fight American forces if they returned. “If they come again, we will stand against them, and we will raise the whole area against them,” he warned. Or in the words of one foreign official in Afghanistan, the Americans went after one guerrilla commander and created a hundred more.

On Tuesday, barely 24 hours after American officials apologized publicly to President Karzai for a previous incident in which 19 civilians were shot by marines in eastern Afghanistan, reports surfaced of at least 21 civilians killed in an airstrike in Helmand Province, though residents reached by phone said the toll could be as high as 80.

While NATO is now in overall command of the military operations in the country, many of the most serious episodes of civilian deaths have involved United States counterterrorism and Special Operations forces that operate separately from the NATO command.

NATO, which now has 35,000 soldiers in the country, has emphasized its concern about keeping civilian casualties to a minimum. Yet NATO, too, has been responsible for civilian casualties over the past year, as it has relied on air power to compensate for a shortage of troops, an American military official who has served in Afghanistan said in a recent interview.

The subject of civilian casualties was the source of intense discussion on Wednesday in Brussels when the NATO secretary general, Jaap de Hoop Scheffer, met with the North Atlantic Council, the top representatives of the coalition. But the conversation was less about how to reduce casualties, according to participants, than about how to explain them to European governments, who say their troops are there for reconstruction, not hunting the Taliban or terrorists.

“The Europeans are worried about a lack of clarity about who is responsible for the counterterror mission,” said one participant in the debate. “They are worried that if NATO appears responsible for these casualties, it will result in a loss of support” for keeping forces in Afghanistan.

But it is not only the Americans whose practices are being questioned. NATO soldiers have frequently fired on civilians on the roads, often because the Afghans drive too close to military convoys or checkpoints.

The public mood hardened against foreign forces in the southern city of Kandahar after British troops fired on civilians while driving through the streets after a suicide bombing last year, and Canadian soldiers have repeatedly killed and wounded civilians while on patrol in civilian areas.

Air Power and Popular Anger

The reliance on air power has led to a string of prominent episodes recently involving the deaths of large numbers of civilians, who often cannot escape, caught between NATO forces and the Taliban and its sympathizers.

Since the beginning of March at least 132 civilians have been killed in at least six bombings or shootings, according to officials. The actual number of civilians killed is probably higher, since the areas of heaviest fighting, like the southern province of Helmand, are too unsafe for travel and many deaths go unreported and cannot be verified.

“You have a bag of capital — that is the good will of the people — and you want to spend that as slow as you could,” said the American military official. “We are spending it at a fearsome rate.”

The issue of civilian casualties has dogged United States-led coalition forces from the beginning of their intervention here in 2001. But as the Taliban surged in strength in 2006, civilians have been caught in the middle more than before, and at a time when Afghans have grown weary of the fighting, said Dr. Sima Samar, director of the Afghan Independent Human Rights Commission.

“If we still have civilian casualties, it can be used by the opposition groups to the government to encourage the people against the government and against the international community,” Dr. Samar said at a recent news conference. “That's why we are concerned, and we ask the international community and the Afghan government to be very, very careful.”

Now in Afghanistan, calls are growing for more political control over military operations.

This week Afghan's upper house of Parliament recommended that the government start peace talks with the Taliban, and that foreign forces cease all offensive operations. While the chances of passage as worded are unlikely, the proposal was one measure of the rising popular anger.

The episode here in this valley in Shindand district in late April showed just how changeable the attitudes toward foreign troops can be.

The ethnic Pashtuns who live in the Zerkoh Valley are from a fiercely independent tribe, surrounded by local enemies, and with a record of fighting all comers. Still, NATO and United States soldiers were a common — even friendly — sight in this valley in western Afghanistan. They came and talked to the tribal leaders, built schools and culverts, and had plans for a new bridge.

A senior Bush administration official said American Special Forces units were conducting an operation in the valley in late April. After the Taliban pinned them down in a firefight, the airstrike was necessary, the military official said. “It was the only way to extract our guys,” the official said.

“If your mortars are not getting you out, you call in close air support and that will be less precise,” said one senior American official who follows the action in Afghanistan closely. “We know that the Taliban hide in villages. The job that we have not done as well is making it clear to European publics that it's the Taliban who are exploiting the civilians.”

A Complicated Environment

But the Americans had stepped into a complicated political environment. In interviews, villagers, who had cooperated with NATO before, blamed local rivals for planting false information with the Americans, to encourage the Americans to attack Zerkoh.

After the Special Forces units started raiding homes, the villagers were so angered, they said, they fought the Americans themselves. They insisted that no Taliban were here, an area that has been mostly calm.

“NATO was coming regularly, and the Afghan Army and police, and we were cooperating with them,” said Muhammad Alef, 35, a farmer who was tending to his wounded cousin in the provincial hospital in the city of Herat.

“But when the Americans came without permission, and they came more than once and disturbed the people,” he said. “They searched the houses, and the second time they arrested people, and the third time the people got angry and fought them.”

The American forces searched the tribal chief's house and arrested two of his staff members, the villagers said. One, a watchman named only Bahadullah, 45, said he had been handcuffed, covered with a hood and taken to the nearby American base at Shindand.

He said he had been strung up by his feet for what seemed like an hour and a half as American soldiers swung him about. When he was let down the soldiers kicked and beat him, he said. In an interview this week, he said he was still passing blood and in pain from the beatings.

A United States military spokesman at Bagram air base north of Kabul, Maj. Chris Belcher, denied in an e-mail message that Afghan or American Special Forces units had entered the villages or detained anyone.

The American forces did not find any weapons caches in the Shindand area, either, he said. They were attacked with small-arms fire, rocket-propelled grenades and mortar shells, he said.

A senior American military official who has looked at what happened in Zerkoh said that some compounds were bombed but added that the troops were receiving fire from them.

But a villager, Abdul Waheed, said the Americans had searched his family compound and found no weapons and certainly must have seen the women and children. Two days later they bombed the compound, killing six children, he said.

“The Americans should leave Afghanistan because this is my own home,” he said. “I am sitting here and they come and just order a bomb to drop.”

Whether there was firing from the compound or not, the military official said tactics needed to be reviewed. “We just have to go over each one of these, one by one, and say even if this was within the rules, is this what we want to do next time,” the official said.

Villagers said the first fighting broke out on April 27, as they had gathered at the bazaar in the central village of Parmakan. Two old men, Adel Shah, 80, who was walking home with some meat and sugar for his family, and Sarwar, 80, who was harvesting poppies, were shot dead by the Americans, said Abdul Zaher, Mr. Shah's son.

A Village Under Fire

That night, the first airstrikes were carried out, mainly on Bakhtabad, the village at the entrance to the valley, residents said. On April 29, the Americans returned, positioning their armored vehicles outside Parmakan.

Villagers said they thought the Americans were going to raid houses again, and the men gathered to fight. Husi, 35, lives in a house near the school and on the edge of the village. She was alone with her 10 children, and when the shooting started they cowered at the entrance of their walled home, she said.

Then suddenly a plane bombed the five-room house. “When they bombed I just ran,” she recalled as she held her 1-year-old boy. Women and children were pouring out of the village to the river to cross it to safety, she said.

In the panic as they fled, Husi was separated from three of her children, Amina, 8, Tote, 5, and Fazli, 3, who are still missing.

“We ran with bare feet, we left our shoes,” said Sara, a relative and the mother of seven, whose house was also bombed. “I was running and they were shooting at us from the plane,” she said.

Two uncles and two cousins were killed when the house was bombed, she said. “We have nothing, it's all finished,” she said.

The river was chest-high at the time, and a number of women and children were swept away. Fifty-seven people died over all, including 17 children under 10, 10 women and 14 old men, Hajji Daulat Khan said. Eight people are still missing, including a 21-year-old man, and Husi's three children.

The bombing of the village so outraged people that they continued fighting the Americans even after the airstrikes. American and Afghan military officials admitted that they had been surprised at the ferocity of the response, and said that at one point American soldiers had been forced to call in the Afghan Army.

“We are not saying that the foreigners should leave or stay, we are just saying they should not do this,” said a farmer, Fateh Muhammad, 55, gesturing with his scythe at an enormous bomb crater and his neighbor's collapsed house. He showed the place where two of his neighbors had been killed in a field nearby.

The airstrikes damaged about 100 homes and a new school built by Italian troops.

“This is a big mistake the Americans are making,” said Nasrullah Khan, a younger brother of the tribal chief, Hajji Daulat Khan. “If the Americans are here for peace, this is not the way.”

Carlotta Gall reported from Zerkoh, and David E. Sanger from Brussels. Taimoor Shah contributed reporting from Zerkoh, and Abdul Waheed Wafa from Kabul.